Improvement in annealing-furnaces



UNITED STATES SELF AND E. C. HAMMER, OF SAME PLACE.

IMPROVEMENT IN ANNEALlNG-FURNACES.

Specification forming part of' Letters Patent No.122,604, dated January9, 1872.

.To all whom it may concern:

Be it known that I, THoRvALD F. HAM- MER, of Branford, in the county ofNew Haven and State of Connecticut, have invented a new Improvement inAnnealing-Furnace 5 and I do hereby declare the following, when taken inconnection with the accompanying drawing and the letters of referencemarked thereon, to be a full, clear, and exact description of the same,and which said drawing constitutes part of this specification andrepresents, in-

Figure l, a perspective view; and in Fig. 2, a longitudinal centralsection.

This invention relates to an improvement in what are commonly calledannealing-furnaces, specially designed for the manufacture of malleableironthat is, furnaces in which the fine is below the floor of theannealing-chamber. The long-continued heat to which this class offurnaces is subjected before the contents are in a condition to beremoved so thoroughly heats all parts ofthe furnace that days arerequired to cool the furnace suciently to enable the Workman to performa second operation. To overcome this loss of time, and ventilate thefurnace as it maybe required at other times than f'or cooling, is theobject of my invention; and it consists in constructing an openin g oropenings through the dome or highest point of furnace, which, incombination With the charging-doors or openings in the ends of thefurnace, when both the doors and opening or openings are open, creates acirculuation of air Within the furnace to greatly facilitate the coolingof the furnace. v

A is the front; B B, the sides; C, the dome 5 and D, the iiue of acommon annealing-furnace.

The length of the furnace depends upon circumstances; and the furnace isprovided at 011e or both ends with a charging-door or opening, E.

Heretofore the only openings into the an- 4 nealing-chamber have beenthrough the chargingdoors; and when the charge is drawn these doors areopen to cool the chamber, Which ordinarily requires several days beforethe chamber is so far cool as to permit the workman to enter the furnacefor repairs or recharging.

In my invention I form one or more openings, F F, through the dome orhighest point of the chamber, which openings are closed by any suitablecovers, and which, when the charge is drawn, are opened; the result ofwhich is that a draught is immediately created through thecharging-openings to the opening in the top, the higher openingpermitting air to pass freely out, thus maintaining a constantcirculation of fresh air, Which greatly aids in cooling the furnace,saving, in the common furnace, forty-eight hours time, as, with thisfree ,circulation of air, the Workman can operate Within the furnaceWhile the Walls are at a comparatively high temperature.

To facilitate this ventilation, pipes may be attached to lead to anyconvenient iiue to increase the draught of air through the furnace.

I claim as my invention- In annealing-furnaces, the combination of oneor more openings through or near the dome or top of' the furnace withthe charging-doors below, in the manner and for the purposesubstantially as described.

T. F. HAMMER.

` Witnesses:

A. J. TIBBITS, J. H. SHUMWAY. (85)

